Bending method and bending device

ABSTRACT

The possibility of performing a bending process again on an area that has already been bent once is reduced. Provided is a bending device including two receiving sections disposed with a distance therebetween; a pressing section that presses a plate-like workpiece, which is supported in a bridged manner between the receiving sections, into a space between the receiving sections; an operable section that applies an external force for causing the pressing section to generate a pressing force; and a marker retaining section that is attached to at least one of the pressing section and the receiving section side and that retains a marker to be adhered to a pressed area of whichever one of surfaces of the workpiece by means of the pressing force.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of International Application PCT/JP2014/074473,with an international filing date of Sep. 17, 2014, which is herebyincorporated by reference herein in its entirety. This applicationclaims the benefit of Japanese Patent Application No. 2013-220028, filedon Oct. 23, 2013, the content of which is incorporated herein byreference.

TECHNICAL FIELD

The present invention relates to bending methods and bending devices.

BACKGROUND ART

In the related art, a known processing tool includes two receivingprotrusions spaced apart from each other such that an osteosynthesisplate can be bridged therebetween, and a pressing section that movestoward an area between the receiving protrusions. The osteosynthesisplate supported between the receiving protrusions is bent by sandwichingthe osteosynthesis plate between the pressing section and the receivingprotrusions and pressing against the osteosynthesis plate using thepressing section (for example, see Patent Literature 1).

The material of the osteosynthesis plate expected to be used with theprocessing tool in Patent Literature 1 is a material with hightoughness, such as stainless steel or a titanium alloy. In a case wherea highly fragile material, such as magnesium or a magnesium alloy, isused as the osteosynthesis plate, if the bending process is performedagain on an area that has already been bent once, the osteosynthesisplate may easily break due to repeated plastic deformation. Inparticular, for example, if the same area is bent in the reversedirection after a fine bending process that is difficult to visuallyrecognize, the material may break.

CITATION LIST Patent Literature {PTL 1} Publication of Japanese PatentNo. 4071563 SUMMARY OF INVENTION

An aspect of the present invention is a bending method including asetting step for setting a plate-like workpiece in a bridged mannerbetween two receiving sections disposed with a distance therebetween,and a pressing step for causing a pressing force to act on a pressingsection so as to press the workpiece set between the receiving sectionsinto a space between the receiving sections. The pressing step includescausing a marker to adhere to a pressed area of whichever one ofsurfaces of the workpiece. The marker indicates that the area has beenpressed.

Another aspect of the present invention is a bending device includingtwo receiving sections disposed with a distance therebetween; a pressingsection that presses a plate-like workpiece, which is supported in abridged manner between the receiving sections, toward an area betweenthe receiving sections; an operable section that applies an externalforce for causing the pressing section to generate a pressing force; anda marker retaining section that is attached to at least one of thepressing section and the receiving section side and that retains amarker to be adhered to a pressed area of whichever one of surfaces ofthe workpiece by means of the pressing force.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view illustrating a bending device according to anembodiment of the present invention.

FIG. 2A is a perspective view illustrating a state where the distancebetween a pressing section and receiving sections of the bending devicein FIG. 1 is increased.

FIG. 2B is a perspective view illustrating a state where the distancebetween a pressing section and receiving sections of the bending devicein FIG. 1 is reduced.

FIG. 3 is a perspective view illustrating a workpiece that has been bentby using the bending device in FIG. 1.

FIG. 4 is a perspective view illustrating a first modification of amarker retaining section of the bending device in FIG. 1.

FIG. 5 is a perspective view illustrating a second modification of themarker retaining section of the bending device in FIG. 1.

FIG. 6 is a perspective view illustrating a workpiece that has been bentby using the bending device in FIG. 5.

FIG. 7A is a vertical sectional view illustrating the secondmodification of the marker retaining section of the bending device inFIG. 1, showing the marker retaining section in an attached state.

FIG. 7B is a vertical sectional view illustrating the secondmodification of the marker retaining section of the bending device inFIG. 1, showing the marker retaining section in a detached state.

FIG. 8A is a vertical sectional view illustrating a third modificationof the marker retaining section of the bending device in FIG. 1, showingthe marker retaining section in an attached state.

FIG. 8B is a vertical sectional view illustrating the third modificationof the marker retaining section of the bending device in FIG. 1, showingthe marker retaining section in a detached state.

FIG. 9A is a vertical sectional view illustrating a fourth modificationof the marker retaining section of the bending device in FIG. 1, showingthe marker retaining section in an attached state.

FIG. 9B is a vertical sectional view illustrating the fourthmodification of the marker retaining section of the bending device inFIG. 1, showing the marker retaining section in a detached state.

FIG. 10A is a plan view illustrating a modification of the bendingdevice in FIG. 1, showing a part thereof provided with a misalignmentprevention mechanism.

FIG. 10B is a front view illustrating the modification of the bendingdevice in FIG. 1, showing the part thereof provided with themisalignment prevention mechanism.

DESCRIPTION OF EMBODIMENTS

A bending device 1 according to an embodiment of the present inventionwill be described below with reference to the drawings.

As shown in FIG. 1, the bending device 1 according to this embodimentincludes two components 3 and 4 connected to each other in a pivotablemanner about a pivot shaft 2. First ends of the two components 3 and 4are respectively provided with grip sections 5 and 6 (operable sections)that are to be gripped by a physician with one hand. As shown in FIGS.2A and 2B, a second end of the first component 3 is provided with twoplanar receiving sections 8 spaced apart from each other with a groove7, which substantially has a semicircular shape in cross section,interposed therebetween. A second end of the second component 4 isprovided with a columnar pressing section 9, which is to be moved to aposition where it engages with the groove 7 by pivoting the twocomponents 3 and 4 relatively to each other.

As shown in FIG. 2A, the pressing section 9 of the bending device 1according to this embodiment is provided with a marker retaining section10. The marker retaining section 10 has a porous structure havingmultiple pores formed in the surface of the columnar pressing section 9.The pores of the porous structure retain powdery markers M therein. Inthis embodiment, the marker retaining section 10 is partially providedin a region that faces the groove 7 at the receiving section 8 side.

The powdery markers M used are preferably composed of a coloredbiocompatible material, such as (white-colored) biocompatible ceramicpowder composed of, for example, calcium phosphate or magnesiumphosphate.

A bending method using the bending device 1 according to this embodimenthaving the above-described configuration will be described below.

In order to bend a plate-like workpiece A by using the bending device 1according to this embodiment, the plate-like workpiece A is set in abridged manner between the two receiving sections 8, as shown in FIG. 2A(setting step). By gripping the grip sections 5 and 6, a pressing forceacts on the pressing section 9 so that the workpiece A set on thereceiving sections 8 is pressed into the space between the two receivingsections 8, as shown in FIG. 2B (pressing step).

Because the pressing section 9 is provided with the marker retainingsection 10 and the markers M are retained within the marker retainingsection 10, when the workpiece A is pressed as a result of the pressingsection 9 being pressed against the surface of the workpiece A, themarkers M retained in the marker retaining section 10 are transferred tothe area of the workpiece A pressed by the pressing section 9. Thus,even when the bending is slight, the operator performing the bendingprocess can easily recognize an already-bent area by simplyvisually-checking the markers M adhered to the surface of the workpieceA.

As a result, the bending device 1 and the bending method according tothis embodiment are advantageous in that the workpiece A can beprevented from breaking as a result of performing a bending processagain on an area that has already been bent once.

Furthermore, because the marker retaining section 10 is provided in thepressing section 9 in the bending device 1 and the bending methodaccording to this embodiment, the markers M adhere to the recessed sideof the bent workpiece A, as shown in FIG. 3. Therefore, the bent areacan be readily recognized by visually checking the markers M on therecessed side of the workpiece A.

Furthermore, because the markers M used are composed of a biocompatiblematerial in this embodiment, if the workpiece A used is to be implantedinto the living body, like an osteosynthesis plate, the workpiece A canbe implanted into the living body without having to remove the markers Madhered thereto after the bending process. Therefore, the operator, suchas a physician, can omit the process for cleaning off the markers M.

Although the markers M to be adhered to the surface of the workpiece Aare described as being powder in this embodiment, a liquid composed of abiocompatible material, such as a (black-colored) povidone-iodineliquid, may be used as an alternative.

Furthermore, although a colored biocompatible material, such as(white-colored) biocompatible ceramic powder composed of, for example,calcium phosphate or magnesium phosphate or a (black-colored)povidone-iodine liquid, is used, the markers M do not have to bebiocompatible if the workpiece A is not intended to be implanted intothe living body, like an osteosynthesis plate. Moreover, even if theworkpiece A is intended to be implanted into the living body, themarkers M do not have to be biocompatible so long as they can be cleanedoff before the implantation. Furthermore, the markers M may be colorlessif they are visually recognizable in the adhered state (based on, forexample, a state in which they bulge out from the surface of theworkpiece A).

Furthermore, in the bending device 1 according to this embodiment, themarker retaining section 10 is provided in a part of the columnarpressing section 9, in the circumferential direction thereof, at aposition that faces the groove 7. Alternatively, as shown in FIG. 4, themarker retaining section 10 may be provided around the entirecircumference of the pressing section 9.

Furthermore, although the marker retaining section 10 is provided in thepressing section 9 in this embodiment, the marker retaining section 10may alternatively be provided at the receiving section 8 side, as shownin FIG. 5.

In the case where the marker retaining section 10 is provided at thereceiving section 8 side, the marker retaining section 10 is preferablydisposed at the bottom of the groove 7, as shown in FIG. 5. When theapex of the protruding side of the workpiece A bent as a result of thebending process comes into contact with the marker retaining section 10,the markers M adhere to the protruding side. Therefore, as shown in FIG.6, the operator can visually check the markers M adhered to theprotruding side of the workpiece A so as to readily recognize the bentarea.

Furthermore, the pressing section 9 and the receiving section 8 side mayboth be provided with marker retaining sections 10. According to thisconfiguration, the markers M adhere to the opposite surfaces of theworkpiece A so that the operator can identify the bent area by lookingat either one of the surfaces.

Furthermore, the marker retaining section 10 may be provided in adetachable manner in the pressing section 9 or at the receiving section8 side. As a method for making the marker retaining section 10detachable from the pressing section 9, a method of attaching the markerretaining section 10 by means of screws 11 and 12, as shown in FIGS. 7Aand 7B, or a method of fitting the marker retaining section 10, like acap, around a core 9 a disposed in the pressing section 9, as shown inFIGS. 8A and 8B, may be employed.

Accordingly, without having to sterilize the marker retaining section10, the bending process can be performed on a plurality of workpieces byreplacing the marker retaining section 10. Moreover, when the markers Mretained in the marker retaining section 10 are used up as a result ofrepeating the bending process, the markers M can be readily resuppliedby simply replacing the marker retaining section 10.

In either case, the marker retaining section 10 disposed around thesurface of the core 9 a constituting the pressing section 9 increasesthe strength of the pressing section 9, thereby allowing for a stablebending process.

As a method of providing the marker retaining section 10 in a detachablemanner at the receiving section 8 side, a unit 14 having the markerretaining section 10 fixed to a base 13 may be attached to the receivingsections 8 by being fitted therebetween, as shown in FIGS. 9A and 9B.

Furthermore, the bending device 1 according to this embodiment may beequipped with a misalignment prevention mechanism 15 that prevents thepressing section 9 and the receiving sections 8 from being misalignedwith the workpiece A during the bending process.

In a case where the workpiece A is a plate that has holes B at theopposite sides of an area where the workpiece A is to be bent, as shownin FIG. 10A, the misalignment prevention mechanism 15 may be constitutedof, for example, handles 16, which have claws 16 a to be fitted into theholes B, attached to the opposite sides of the pressing section 9 in apivotable manner about axes 17 extending parallel to the longitudinalaxis of the pressing section 9.

In the bending device 1 having such a misalignment prevention mechanism15, when the pressing section 9 is moved closer toward the groove 7between the receiving sections 8 by operating the grip sections 5 and 6in a state where the workpiece A is set in a bridged manner between thereceiving sections 8, as shown in FIG. 10B, the handles 16 disposed atthe opposite sides of the pressing section 9 also move closer to theworkpiece A. By bringing the pressing section 9 even closer to thegroove 7, the claws 16 a provided in the handles 16 become fitted intothe holes B in the workpiece A, and the pressing section 9 subsequentlycomes into contact with the surface of the workpiece A.

Therefore, even when a pressing force is applied from the pressingsection 9 to the workpiece A and the bending process is performedthereon, since the claws 16 a of the handles 16 are fitted in the holesB in the workpiece A, the workpiece A is positioned so as to beprevented from being misaligned with the pressing section 9 and thereceiving sections 8. Moreover, when the bending process is performed,the positions of the holes B change as a result of the bent workpiece A.However, since the handles 16 pivot about the axes 17 in correspondencewith this positional change, the positions of the claws 16 a also changeso that the claws 16 a are maintained in the fitted state in the holesB. Consequently, the workpiece A is supported without being misalignedwith the pressing section 9 and the receiving sections 8 even during thebending process.

From the above-described embodiment and modifications thereof, thefollowing aspects of invention are derived.

An aspect of the present invention provides a bending method including asetting step for setting a plate-like workpiece in a bridged mannerbetween two receiving sections disposed with a distance therebetween,and a pressing step for causing a pressing force to act on a pressingsection so as to press the workpiece set between the receiving sectionsinto a space between the receiving sections. The pressing step includescausing a marker to adhere to a pressed area of whichever one ofsurfaces of the workpiece. The marker indicates that the area has beenpressed.

According to this aspect, when the plate-like workpiece is supported bythe two receiving sections so as to bridge between the two receivingsections in the setting step and the pressing section is moved towardthe space between the receiving sections in the pressing step, theworkpiece is pressed by the pressing section, and a bending process forthe workpiece thus commences. When a pressing force is applied from thepressing section to the workpiece disposed between the pressing sectionand the receiving sections, the marker adheres to the pressed area ofwhichever one of the surfaces of the workpiece. Thus, an operator canrecognize that the area has already been bent once based on the adheredmarker even if the bending of the workpiece is too slight to be visuallyrecognized. Then, by checking the marker, the operator can readilyprevent another bending process from being performed again on the areato which the marker is adhered.

In the above aspect, the pressing step may include disposing the markerat the pressing section side of the workpiece and causing the marker toadhere to the surface of the workpiece by means of the pressing force.

Accordingly, since the marker adheres to the surface of the workpiecepressed by the pressing section, the bent position can be confirmed inthe surface that is recessed after the bending process. In this case,the meaning of the expression “disposing the marker at the pressingsection side of the workpiece” includes disposing a marker carryingmember, such as a sheet, at a position interposed between the pressingsection and the workpiece, in addition to allowing the pressing sectionused for performing the bending process to retain the marker. In eithercase, the marker indicating the bent area can be adhered to the surfaceof the workpiece.

In the above aspect, the pressing step may include pressing against theworkpiece by using the pressing section, which retains the marker on asurface thereof at the workpiece side.

Accordingly, the marker can be adhered to the workpiece by simplysandwiching the workpiece between the pressing section and the receivingsections and pressing against the workpiece, thereby allowing for asimple bending process.

In the above aspect, the pressing step may include disposing the markerat the receiving section side of the workpiece and causing the marker toadhere to the surface of the workpiece by means of the pressing force.

Accordingly, because the marker adheres to the surface at the receivingsection side of the workpiece, the bent position can be confirmed in thesurface that becomes a protruding side after the bending process. Inthis case, the meaning of the expression “disposing the marker at thereceiving section side of the workpiece” includes disposing a markercarrying member, such as a sheet, at a position interposed between thereceiving sections and the workpiece, in addition to allowing thereceiving sections used for performing the bending process to retain themarker. In either case, the marker indicating the bent area can beadhered to the surface of the workpiece.

In the above aspect, the workpiece may be an osteosynthesis plate, andthe marker may be composed of a biocompatible material.

Accordingly, it is possible to manufacture an osteosynthesis plate thatcan be applied to bones without having to remove the marker afterperforming the bending process.

Another aspect of the present invention provides a bending deviceincluding two receiving sections disposed with a distance therebetween;a pressing section that presses a plate-like workpiece, which issupported in a bridged manner between the receiving sections, toward anarea between the receiving sections; an operable section that applies anexternal force for causing the pressing section to generate a pressingforce; and a marker retaining section that is attached to at least oneof the pressing section and the receiving section side and that retainsa marker to be adhered to a pressed area of whichever one of surfaces ofthe workpiece by means of the pressing force.

According to this aspect, when the plate-like workpiece is supported bythe two receiving sections so as to bridge between the two receivingsections and an external force is applied to the pressing section, theworkpiece is pressed by the pressing section toward the space betweenthe receiving sections, and a bending process for the workpiece thuscommences. As the external force applied to the manual operable sectionis increased, the pressing force increases, so as to cause the materialconstituting the workpiece to exceed the elastic range and enter theplastic range, whereby the workpiece plastically deforms.

In this case, when the pressing force acts on the workpiece from thepressing section or the receiving section side, the marker retained inthe marker retaining section attached to at least one of the pressingsection and the receiving section side adheres to the pressed area ofwhichever one of the surfaces of the workpiece. Thus, even when a finebending process is performed, the bent position can be identified basedon the adhered marker, so that a warning can be given to prevent abending process from being performed again on an area that has alreadybeen bent once.

In the above aspect, the marker retaining section may be detachablyattached to at least one of the pressing section and the receivingsection side.

Accordingly, in a case where the marker retained in the marker retainingsection decreases as a result of performing the bending process, themarker retaining section may be detached and be replaced with a newmarker retaining section, so that the bending process can becontinuously performed while causing the marker to adhere to the bentarea.

In the above aspect, the marker may be formed of powder or liquid, andthe marker retaining section may have a porous structure that is capableof retaining the marker within pores.

Accordingly, the marker can be readily retained within the pores in theporous marker retaining section, so that the marker formed of powder orliquid can be readily transferred onto the surface of the workpiece whena pressing force is applied.

In the above aspect, the marker retaining section may be attached to asurface at the receiving-section side of the pressing section.

Accordingly, since the marker adheres to the surface of the workpiece tobe pressed by the pressing section, the bent position can be confirmedin the surface that is recessed after the bending process.

In the above aspect, the marker retaining section may be attachedbetween the two receiving sections.

Accordingly, because the marker adheres to the surface at the receivingsection side of the workpiece, the bent position can be confirmed in thesurface that becomes a protruding side after the bending process.

In the above aspect, the workpiece may be an osteosynthesis plate, andthe marker may be composed of a biocompatible material.

Accordingly, it is possible to process an osteosynthesis plate that canbe applied to bones without having to remove the marker after performingthe bending process.

REFERENCE SIGNS LIST

-   A workpiece-   M markers-   1 bending device-   5, 6 grip sections (operable sections)-   8 receiving sections-   9 pressing section-   10 marker retaining section

1. A bending method comprising: a setting step for setting a plate-likeworkpiece in a bridged manner between two receiving sections disposedwith a distance therebetween; and a pressing step for causing a pressingforce to act on a pressing section so as to press the workpiece setbetween the receiving sections into a space between the receivingsections, wherein the pressing step includes causing a marker to adhereto a pressed area of whichever one of surfaces of the workpiece, themarker indicating that the area has been pressed.
 2. The bending methodaccording to claim 1, wherein the pressing step includes disposing themarker at the pressing section side of the workpiece and causing themarker to adhere to the surface of the workpiece by means of thepressing force.
 3. The bending method according to claim 2, wherein thepressing step includes pressing against the workpiece by using thepressing section, which retains the marker on a surface thereof at theworkpiece side.
 4. The bending method according to claim 1, wherein thepressing step includes disposing the marker at the receiving sectionside of the workpiece and causing the marker to adhere to the surface ofthe workpiece by means of the pressing force.
 5. The bending methodaccording to claim 1, wherein the workpiece is an osteosynthesis plate,and wherein the marker is composed of a biocompatible material.
 6. Abending device comprising: two receiving sections disposed with adistance therebetween; a pressing section that presses a plate-likeworkpiece, which is supported in a bridged manner between the receivingsections, into a space between the receiving sections; an operablesection that applies an external force for causing the pressing sectionto generate a pressing force; and a marker retaining section that isattached to at least one of the pressing section and the receivingsection side and that retains a marker to be adhered to a pressed areaof whichever one of surfaces of the workpiece by means of the pressingforce.
 7. The bending device according to claim 6, wherein the markerretaining section is detachably attached to at least one of the pressingsection and the receiving section side.
 8. The bending device accordingto claim 6, wherein the marker is formed of powder or liquid, whereinthe marker retaining section has a porous structure that is capable ofretaining the marker within pores.
 9. The bending device according toclaim 6, wherein the marker retaining section is attached to a surfaceat the receiving-section side of the pressing section.
 10. The bendingdevice according to claim 6, wherein the marker retaining section isattached between the two receiving sections.
 11. The bending deviceaccording to claim 6, wherein the workpiece is an osteosynthesis plate,and wherein the marker is composed of a biocompatible material.